/*
 * Copyright (c) 2024 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { ts, NodePredicate } from "qvog-dsl";
import { native, HomeCheckHint } from "qvog-dsl";

const SEVERITY = 2;
const DOC_PATH = '';
const DESCRIPTION = 'Disallow unnecessary catch clauses.';


export const CatchClause: NodePredicate<ts.CatchClause> = {
    is(node: ts.Node): node is ts.CatchClause {
        return ts.isCatchClause(node);
    },
};

export default native<HomeCheckHint>()()
    .match(CatchClause)
    .when((node: ts.CatchClause): boolean => {
        if (node.block.statements.length !== 1) {
            return false;
        };

        const stmt = node.block.statements[0];
        if (!ts.isThrowStatement(stmt) || !stmt.expression || !ts.isIdentifier(stmt.expression)) {
            return false;
        };

        const catchVariable = node.variableDeclaration?.name;
        if (!catchVariable || !ts.isIdentifier(catchVariable) || stmt.expression.text !== catchVariable.text) {
            return false;
        };

        return addWarningForCatchClause(node);
    })
    .report({
        severity: SEVERITY,
        description: DESCRIPTION,
        docPath: DOC_PATH,
    });


function addWarningForCatchClause(node: ts.CatchClause): boolean {
    const parentTryStatement = node.parent;
    if (!ts.isTryStatement(parentTryStatement)) {
        return false;
    };
    return true;
}

